Alert archive / Montana / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 2, NWS Great Falls, MT

May 22, 1998Chouteau County, Fergus County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at May 22, 1998, 4:03 PM MDT for Chouteau County, Fergus County, Montana. It was in force for 47 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
May 22, 1998, 4:03 PM MDT (22:03 UTC)
Expired
May 22, 1998, 4:50 PM MDT
In force
47 min
Issued by
NWS Great Falls, MT
Area
Whole counties

Counties Chouteau County, MT, Fergus County, MT

The radar

The Great Falls radar (KTFX), 118 km from the middle of the area, began a volume at 22:03 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Great_falls, MT (KTFX), launched 12:00Z, 10.1 hours before the alert went out and 59 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Great_falls, MT at 12:00Z on 1998-05-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Great_falls, MT at 12:00Z on 1998-05-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 11 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
1 J/kg
Mixed-layer CIN
-42 J/kg
Mixed-layer LCL
724 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
11 m²/s²
0-3 km storm-relative helicity
80 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

626 
WUUS1 KGTF 222208 RRA
SVRGTF
MTC015-027-222250-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
403 PM MDT FRI MAY 22 1998


THE NATIONAL WEATHER SERVICE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR
  SOUTHEASTERN CHOUTEAU COUNTY IN NORTH CENTRAL MONTANA
  NORTHWESTERN FERGUS COUNTY IN CENTRAL MONTANA

* UNTIL 450 PM MDT


  * AT 400 PM MDT... A RAPIDLY DEVELOPING THUNDERSTORM WAS INDICATED
    35 MILES NORTHWEST OF LEWISTOWN OR 19 MILES SOUTH OF ILIAD
    AREA... BY DOPPLER RADAR AT GREAT FALLS... MOVING NORTHWEST 20
    MPH.

  * SOME LOCATIONS IN OR NEAR THE PATH OF THIS STORM ARE... ILIAD
    AREA.

The office that day

Everything else NWS Great Falls, MT issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 22, 3:42 PM MDTSevere Thunderstorm WarningTFXPondera, Teton58 min

Nearby

Severe Thunderstorm Warnings in Montana, 1998Every severe thunderstorm warning in 1998

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.